core:  [RFE] Restart HA VMs ASAP

[RFE] Restart HA VMs when power management reports host is in powered off state

This patch changes the following flows

1) soft-fencing : if Host has PM configured, check host status and if it
is off , skip soft-fencing and put host status to DOWN
2) Restart : if Host has PM configured, check host status and if it
is off , skip the stop command and put host status to DOWN

The result of that is a faster HA VMs release on the fenced host and
restart on another host saving us unnecessary retries and wait time.

Change-Id: Iaca0111d13a625014fb424bdccd3709b8ea03382
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1058737
Signed-off-by: Eli Mesika <emesika@redhat.com>